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An AGN can have
several different structures.

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The brightest feature
is the accretion disk.

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In this Event Horizon
Telescope radio image,

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we see the accretion
disk around a supermassive

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black hole called M87*.

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This plane of gas and dust
orbits the black hole

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and heats up through
gravitational and frictional forces.

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Above and below the disk,

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an AGN can have a corona.

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This superheated plasma of loose electrons emits a lot of X-rays.

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It's way less dense than the
accretion disk but way hotter.

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Despite AGN being some of the
brightest objects in the universe,

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they can also
sometimes hide behind

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a dusty torus.

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Now a torus is a thick,
bagel-shaped structure

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that is so dense we can't see the AGN

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unless the bagel’s hole is facing
one of our telescopes

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or you seek the energetic
X-ray signals.

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Now scientists
using NASA's
NuSTAR mission

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think that as many as
50% of black holes

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are obscured by a torus.

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All of that is nothing

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compared to the achievements

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of a jet!

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See that?

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That bright line is a black hole

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throwing a huge jet of particles

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moving at nearly the speed of light.